iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

platform/x86: alienware-wmi: fix kfree on potentially uninitialized pointer

Browse Source 
commit 98e2630284ab741804bd0713e932e725466f2f84 upstream.

Currently the kfree of output.pointer can be potentially freeing
an uninitalized pointer in the case where out_data is NULL. Fix this
by reworking the case where out_data is not-null to perform the
ACPI status check and also the kfree of outpoint.pointer in one block
and hence ensuring the pointer is only freed when it has been used.

Also replace the if (ptr != NULL) idiom with just if (ptr).

Fixes: ff0e9f26288d ("platform/x86: alienware-wmi: Correct a memory leak")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Colin Ian King 2019-03-30 00:17:12 +00:00 committed by Greg Kroah-Hartman
parent eff8c0335c
commit 5307944aa5
1 changed files with 8 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
drivers/platform/x86/alienware-wmi.c
View File

@ -504,23 +504,22 @@ static acpi_status alienware_wmax_command(struct wmax_basic_args *in_args,
input.length = (acpi_size) sizeof(*in_args);
input.pointer = in_args;
if (out_data != NULL) {
if (out_data) {
output.length = ACPI_ALLOCATE_BUFFER;
output.pointer = NULL;
status = wmi_evaluate_method(WMAX_CONTROL_GUID, 1,
command, &input, &output);
} else
if (ACPI_SUCCESS(status)) {
obj = (union acpi_object *)output.pointer;
if (obj && obj->type == ACPI_TYPE_INTEGER)
*out_data = (u32)obj->integer.value;
}
kfree(output.pointer);
} else {
status = wmi_evaluate_method(WMAX_CONTROL_GUID, 1,
command, &input, NULL);
if (ACPI_SUCCESS(status) && out_data != NULL) {
obj = (union acpi_object *)output.pointer;
if (obj && obj->type == ACPI_TYPE_INTEGER)
*out_data = (u32) obj->integer.value;
}
kfree(output.pointer);
return status;
}
/*